811
Chapter 18
AFCAN Controller
User’s Manual U16580EE3V1UD00
cidental data WR by CPU. Note the storage process may be disturbed (delayed) when the CPU
accesses the message buffer.
Figure 18-28:
DN and MUC Bit Setting Period (for Standard ID Format)
18.9.3 Receive history list function
The receive history list (RHL) function records in the receive history list the number of the receive mes-
sage buffer in which each data frame or remote frame was received and stored. The RHL consists of
storage elements equivalent to up to 23 messages, the last in-message pointer (LIPT) with the corre-
sponding CnLIPT register and the receive history list get pointer (RGPT) with the corresponding
CnRGPT register.
The RHL is undefined immediately after the transition of the CAN module from the initialization mode to
one of the operation modes.
The CnLIPT register holds the contents of the RHL element indicated by the value of the LIPT pointer
minus 1. By reading the CnLIPT register, therefore, the number of the message buffer that received and
stored a data frame or remote frame first can be checked. The LIPT pointer is utilized as a write pointer
that indicates to what part of the RHL a message buffer number is recorded. Any time a data frame or
remote frame is received and stored, the corresponding message buffer number is recorded to the RHL
element indicated by the LIPT pointer. Each time recording to the RHL has been completed, the LIPT
pointer is automatically incremented. In this way, the number of the message buffer that has received
and stored a frame will be recorded chronologically.
The RGPT pointer is utilized as a read pointer that reads a recorded message buffer number from the
RHL. This pointer indicates the first RHL element that the CPU has not read yet. By reading the
CnRGPT register by software, the number of a message buffer that has received and stored a data
frame or remote frame can be read. Each time a message buffer number is read from the CnRGPT reg-
ister, the RGPT pointer is automatically incremented.
If the value of the RGPT pointer matches the value of the LIPT pointer, the RHPM bit (receive history
list pointer match) of the CnRGPT register is set to 1. This indicates that no message buffer number
that has not been read remains in the RHL. If a new message buffer number is recorded, the LIPT
pointer is incremented and because its value no longer matches the value of the RGPT pointer, the
RHPM bit is cleared. In other words, the numbers of the unread message buffers exist in the RHL.
SOF
(1)
ID
IDE
RTR
R0
DLC
DATA0-DATA7
CRC
ACK EOF
CAN std ID format
(11)
(1)
(1)
(1)
(4)
(0-64)
(16)
(2)
Recessive
Dominant
DN
MUC
Message Store
MDATA,MDLC.MIDx- > MBUF
(7)
Set DN & clear MUC
at the same timing
CINTS1
Set DN & MUC
at the same time
IFS
INTREC1
Operation of the CAN contoroller
Summary of Contents for MuPD70F3187
Page 6: ...6 Preface User s Manual U16580EE3V1UD00 ...
Page 16: ...16 User s Manual U16580EE3V1UD00 ...
Page 28: ...28 User s Manual U16580EE3V1UD00 ...
Page 32: ...32 User s Manual U16580EE3V1UD00 ...
Page 84: ...84 Chapter 2 Pin Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 144: ...144 Chapter 3 CPU Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 312: ...312 Chapter 9 16 Bit Timer Event Counter P User s Manual U16580EE3V1UD00 MEMO ...
Page 534: ...534 Chapter 11 16 bit Timer Event Counter T User s Manual U16580EE3V1UD00 ...
Page 969: ...969 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 970: ...970 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 ...
Page 976: ...976 Chapter 22 Internal RAM Parity Check Function User s Manual U16580EE3V1UD00 MEMO ...
Page 984: ...984 Chapter 23 On Chip Debug Function OCD User s Manual U16580EE3V1UD00 MEMO ...
Page 1006: ...1006 Chapter 24 Flash Memory User s Manual U16580EE3V1UD00 MEMO ...
Page 1036: ...1036 Chapter 27 Recommended Soldering Conditions User s Manual U16580EE3V1UD00 MEMO ...
Page 1046: ...1046 Appendix A Index User s Manual U16580EE3V1UD00 MEMO ...
Page 1052: ...1052 User s Manual U16580EE3V1UD00 ...
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